Packaging apparatus



Feb. 8, 1966 P. P. SPOLSINO PACKAGING APPARATUS 2 Sheets-Sheet 1 Filed Feb. 5, 1965 Fig.2

Feb 8, 1956 P. P. sPoLslNo 3,233,387

PACKAGING APPARATUS Filed Feb. 5, 1965 2 Sheets-Sheet 2 Fig. 3

United States Patent Oce 3,233,387 Patented Feb. 8, 1966 3,233,387 PACKAGING APPARATUS Peter P. Spolsino, Revere, Mass., assigner to W. R. Grace & Co., Duncan, S.C., a corporation of Connecticut Filed Feb. 5, 1963, Ser. No. 256,314 7 Claims. (Cl. 53-393) This invention relates to improved heat shrinking apparatus and particularly to a machine which, without adjustment, change of rollers, or other adaptation will successfully shrink the bag or sheet wrappings of heatshrinkable material which are used to enclose, e.g., retail cnt of meats.

It is now customary to wrap individual cuts of meat in transparent material before placing them in the selfservice display cabinet. Wrapping not only increases the length of time during which meat may be kept in refrigerated, self-service cabinets without deterioration, but it prevents bacteria and molds from reaching the meat as it is constantly handled and examined -by intending purchasers.

It is a great advantage to package meat in a bag or sheet wrapping which tits the cut loosely, since this makes rapid packing possible, and then shrink the wrapping in a subsequent operation until it is drum tight and hugs the meat so closely that frosting inside the wrapper with its consequent loss of transparency does not occur.

It has been found that the most satisfactory method of transferring heat to a heat-shrinkable wrapping is by a hot uid (usually water), for then the proper temperature to-cause shrinking may be simply and accurately controlled. Consequently, after wrapping the meat cut in a heat-shrinking wrapper, the wrapped package is usually drenched with hot water which causes the wrapping to shrink into a drum-tight, transparent condition. It is, of course, necessary that the wrapping be uniformly heated in order to shrink uniformly, and consequently various expedients have been used to insure that the hot water reaches all exposed parts of the package.

One successful way of doing this has been to pass the package between a pair of sponge rollers, at least one of which is saturated with hot water at the time that the package passes through the nip. The tight squeeze that develops as the package passes between the rolls forces water out of the Sponges and pours it over the surface of the package. However, so far as I am aware, these machines have limited adaptability to varying package size, and are suitable for use only in meat-packing estabe lishments where great quantities of relatively uniformly sized packages pass through a machine.

The objects of the invention are to avoid scrimps, foldover, and scufng of the enveloping film, and to produce a water-flooding, heat-shrinking apparatus, which without adjustment and the consequent loss of operators time, may shrink any of the great variety of cuts which are packaged in the usual super-market.

This result is accomplished b-y providing two transport or feed belts, one above the other, which, running at the same surface speed, carry the loosely-wrapped packages into the bite between two highly compressible water-drenching sponge rolls, pivoting the entrance end of the upper belt and operatively connecting the remote end of said belt to the shaft of the upper roll in such a manner that the spacing between the rolls is increased or decreased to accord with the vertical dimension of the package which is passing between the belts towards the rolls. By this arrangement, the machine adjusts itself to packages of varying size and packages of almost any retail cut size may pass between the rolls and be properly shrunk with no adjustment or other requirement for attention on the part of the operator.

In the accompanying drawings,

FIG. 1 illustrates a side elevation of the machine.

FIG. 2 is a top plan view, and

FIG. 3 is an end elevation of the entrance end of the machine (corresponding to the left hand end of FIG- URES 1 and 2).

The machine 10 comprises a table 11 supported by the legs 12f12a. Platform 13, extending between the legs 12-12a, supports the drive motor 14 and a hot water tank 15. Lower feed belt 16, which lies parallel to the top of table 11, is stretched between the 'feed rolls 17 and 18. 'Ihe shaft 19 of roll 17 extends through and is appropriately journaled in a pair of brackets 21--21, which extend outwardly fro-rn the front of the machine. The shaft 22 of roll 18 extends through and is journaled in a pair of vertical extensions 23-23, which are fastened, as by welding, on the edge of table 11.

The front pair of legs 12a extend upwardly lfrom the table top to form supports for the forward drive roll 24 of the upper feed belt 25. Shaft 26 of roll 24 projects to and is appropriately journaled near the top of the extended legs 12a. Two arms 27-27, drilled adjacent their forward end to permit the arms to be hung on the protruding ends of the shaft 26, carry the belt roll 28 at their inboard ends. Shaft 29 of roll 28 extends through and is journaled in each arm 27. Cross tie-rods 31-31 maintain parallelism between the arms.

The upper water-drenching roll 32, which is covered with a thick layer of highly compressible sponge material, e.g., foamed rubber, foamed cellulose acetate, lor any other equivalent material, is supported by shaft 36, which extends through and is journaled in two struts 33-33, which also hold the stub ends of shaft 29. Two guide plates 34-34, which extend upwardly from the table top, are each provided with an arcuate slot 35. The ends of roll shaft 36 project through arms 27 and struts'33 and ride in these slots. Consequently, as the free end of the in-running belt 25 rises or falls, the vertical position of roll 32 is simultaneously shifted up or down.

Lower water-drenching roll 37, similarly covered with a highly compressible sponge material, is supported by shaft 38, which rotates in bearing blocks 39-39 fastened to the top of table 11. The table top is cut away at 41 to allow the lower part of roll 37 to dip into hot water tank 15, which is located directly beneath the cut-out 41. Water in tank 15 is heated and maintained at the proper temperature by the thermostatically controlled electric immersion heater 42.v A constant water level is preferably maintained by a oat-valve 40 or by an equivalent device.

Hot water may be delivered to roll 37 by supporting the roll on a hollow shaft 38 fed by an appropriate pump and piping arrangement e.g., water submersible pump 65 and conduit 66. Similarly, it is preferred that upper roll 32 be fed with hot water fed through flexible hose 67 to a hollow shaft 36 in order to guarantee that a sufiiciency of hot water to shrink the film will be available.

Power is delivered from the motor 14 by belt 43 to a belt pulley 44 fastened to shaft 19. To cause the feed belts 25 and 16 to run at the same surface speed, they are connected by a cogged belt 45, running over pulleys 46 an-d 47, fastened to the respective shafts 26 and 19.

The inboard feed belt rolls are driven by cogged belts 48 and 49, which extend between pulleys 51 and 52 fastened to the outboard shafts 19 and 26, respectively and pulleys 53 and 54 fastened to the respective inboard shafts 22 and 29. The drenching rolls are similarly driven by cogged belts 55 and 56, which pass over pulleys 57 and 59, which are fastened to the inboard roll shafts 29 and 22 and over pulleys 58 and 61 fastened to the drenching roll shafts 36 and 38. In this way the entire system is run at the same surface speed.

Take-away belt 62, which may be separately driven, receives the goods as they emerge from between the rolls 32 and 37 and carries them to a take-off station.

Many package measurements have shown that retail meat cut packages rarely exceed 6% inches in Vertical dimension, but that their range includes almost every dimension between 1A. inch (bacon packs and ham slices) and 6% inches. The present machine automatically adjusts itself over a vertical package-dimension range of to 7 inches. A -counterweight may be fastened to the conveyor frame arm 27 or other well known means may be used to decrease the :weight of the upper conveyor and frame assembly on the package to a desired minimum.

If an undamaged and attractive package is to result, the goods should be moving ahead into the bite at the same speed at which the rolls travel, and the spacing between the rolls should permit the goods to enter the bite Without scufiing, rubbing, or hesitancy.

If these conditions are not met, the loose film covering is folded over and scrirnped-and a fold produces an unsightly, opaque area, and, at the worst, the film may tearlThis machine eliminates this difliculty.- The top and bottom belts travel at the same speed and hence there is no tendency for a scrimp or fold-over to occur. At the same time, the package itself as it travels between the belts wedges the upper roll into the correct position to accept it and pass it through the bite, and because the package and the rolls are travelling at the same speed, there is no tendency for a spin or skid to displace the loose film covering. The easy, enveloping squeeze of their deep foam covering floods the package thoroughly and produces a uniformly skin-tight covering.

I claim:

1. Heat-shrinking apparatus for heat-shrinking film coverings on packages comprising,

(a) two superposed inrunning package feed belts,

(b) a roll stand comprising two counter-rotating compressible sponge rolls the bite of which is located adjacent the delivery end of the belts,

(c) the feed end of the upper belt being pivoted above the lower belt at a distance sufficient to accept the package,

(d) means connecting the upper belt and the upper roll which raise and lower the upper roll in accordance with the angular attitude assumed by said upper belt,

(e) means to flood at least fone of the rolls with hot fluid, and

(f) means driving both belts and both rolls at the same surface speed.

2. Machine as defined in claim 1 wherein the flooding means comprises l (a) a hot water tank located beneath the lower compressible roll and wherein (b) the water in said tank is maintained at a substantially constant level, and

(c) the lower portion of the lower roll dips beneath the water level in said tank.

3. Machine as defined in claim 2 wherein said flooding means further comprises a hollow shaft supporting the upper roll `and means for supplying water to said shaft.

4. A heat shrinking machine as defined in claim 1 wherein the flooding means comprises a hollow shaft supporting at least one of said rolls and means for supplying hot water to each of said shafts.

5. Machine as defined in claim 4 wherein both rolls are supported on a hollow shaft.

6. Machine as claimed in claim 1 wherein (a) the means to maintain equal surface speed of the feed belts and rolls comprises cogged pulley belts interconnecting the belts and rolls and power means driving one of said pulley belts.

7. Apparatus for heat-shrinking lni coverings on packages comprising:

(a) two superposed inrunning package feed belts,

(b) a roll stand comprising two counter-rotating compressible sponge rolls the bite of which is located adjacent the delivery end of the belts,

(c) the feed end of the upper belt being pivoted above the lowerbelt at a distance suliicient to accept the package,

(d) means connecting the upper belt and the upper roll which raises and lowers the upper roll in accordance with the angular attitude assumed by said upper belt,

(e) means to flood at least one of the rolls with hot fluid,

(f) means driving both belts and both rolls at the same surface speed,

(g) the position of the upper roll being guided by arcuate slotted lguide plates located adjacent each end of the roll,

(h) the axle of the roll projecting through each slot,

and

(i) the axle being journaled, inboard of said plates, in a rigid extended arm on each side of the roll, which arms also support the delivery end of the upper belt and are pivoted at the feed end of the upper belt whereby the angular attitude of the upper belt and the height of the upper roll is simultaneously changed in accordance with the vertical dimension of a package passing between the upper and lower belts.

References Cited by the Examiner UNITED STATES PATENTS 2,097,427 11/ 1937 Bergstein 53--38 XR 2,785,519 3/1957 Rumsey 53184 3,115,735 12/1963 Harrison 53-184 B. STICKNEY, Primary Examiner. A. E. FOURNIER, Assistant Examiner. 

1. HEAT-SHRINKING APPARATUS FOR HEAT-SHRINKING FILM COVERINGS ON PACKAGES COMPRISING, (A) TWO SUPERPOSED INRUNNING PACKAGE FEED BELTS, (B) A ROLL STAND COMPRISING TWO COUNTER-ROTATING COMPRESSIBLE SPONGE ROLLS THE BITE OF WHICH IS LOCATED ADJACENT THE DELIVERY END OF THE BELTS, (C) THE FEED END OF THE UPPER BELT BEING PIVOTED ABOVE THE LOWER BELT AT A DISTANCE SUFFICIENT TO ACCEPT THE PACKAGE, (D) MEANS CONNECTING THE UPPER BELT AND THE UPPER ROLL WHICH RAISE AND LOWER THE UPPER ROLL IN ACCORDANCE WITH THE ANGULAR ATTITUDE ASSUMED BY SAID UPPER BELT, (E) MEANS TO FLOOD AT LEAST ONE OF THE ROLLS WITH HOT FLUID, AND (F) MEANS DRIVING BOTH BELTS AND BOTH ROLLS AT THE SAME SURFACE SPEED. 